1. Technical Field
The present invention relates to a mounting structure in which a member, such as an IC, is mounted on a mounting body, such as a substrate, an electro-optical device having the mounting structure, an electro-optical device substrate, and an electronic apparatus having the electro-optical device.
2. Related Art
In electro-optical devices, such as active matrix liquid crystal devices and organic electroluminescent display devices, in general, pixels are provided corresponding to intersections of a plurality of data lines and a plurality of scanning lines, and predetermined signals are supplied to the respective pixels through the data lines and the scanning lines to drive the pixels. Therefore, in the electro-optical devices, a plurality of conductive patterns are formed as signal lines on an electro-optical device substrate having an electro-optical material thereon, and an IC is mounted on the electro-optical device substrate in a COG (Chip On Glass) manner through mounting pads each constituting a portion of the signal lines. In addition, a flexible substrate on which an IC is mounted in a COF manner (Chip On Film) is mounted on the mounting pads of the electro-optical device substrate.
In the electro-optical device, with an increase in the number of pixels or a reduction in pitch between pixels, the pitch of conductive patterns tends to decrease. Therefore, when, for example, water is permeated into the conductive patterns exposed to air, corrosion occurs in the conductive patterns, which causes the conductive patterns to become broken. Therefore, in order to solve the problem of the corrosion occurring in the conductive patterns, there has been proposed a technique of covering the exposed conductive patterns with resin (for example, see Japanese Unexamined Patent Application Publication No. 2003-36039).
Further, in the electro-optical device, before an IC is mounted on the electro-optical device substrate, a test probe comes into contact with the conductive patterns to apply test signals to each pixel, thereby testing the operation of each pixel. Therefore, in the related art, the conductive patterns extend from the mounting pads to a region overlapping the IC in plan view, and the extending portions are used as test pads with which the test probe comes into contact.
However, as disclosed in Japanese Patent Application Publication No. 2003-36039, in a method of covering the conductive patterns with resin, since the resin is coated with low precision, there is a fear that, when the conductive patterns are coated with the resin layer, mounting pads will also be covered with the resin layer. In addition, as in the related art, in a structure in which the test pads are arranged so as to overlap the IC in plan view, when the IC is formed in a small size, it is difficult to accurately mount the test pads.